That Prince was born and bred in Minneapolis, Minnesota, is the kind of detail that, if you were writing a novel, you wouldn't dare make up. That this byword for US white-breadery was home to one of the most creative, unstoppable and polymorphously perverse black artists is a fact you can take a slow walk around to examine from all angles without it ever becoming less perplexing or delicious.

But, as Prince: A Purple Reign (BBC4) duly noted, that is where it all began. He got pop and rock from the local radio station, some inherited gifts from his jazz-singing mother and pianist-and-songwriter father, and after that you can really only look to alchemy for explanation.

Thanks perhaps to the public reticence of its subject who, after a bout of stagefright during one of his first television interviews, has only rarely spoken to any media since, A Purple Reign focused better on the music, its makeup and its contexts than did last week's sycophantic guff about Janet Jackson.

There's a lot to cram into an hour: Prince started playing in his first band, Grand Central, at 15, and got a demo produced by Chris Moon two years later that saw him signed by Owen Husney and then to Warner Records. After that, life became a whirling frenzy of frock coats, funk (and pop and rock and R&B) and all-round fabulousness, with Prince at the centre of the storm cranking out hits, gradually taking more and more control of his music-making.

The latter development brought him into conflict with Warner Bros (which is when he announced that "Prince" was dead and he would henceforth be known simply by a curlicue, a decision that caused more pain to journalists than Warners until they realised it could be rendered as "The Artist Formerly Known as Prince"). Now he pleases himself, releasing and promoting – or not – according to his own schedule, and with enough fans still dazzled by his eclectic and prolific genius to keep him until the end of his days.